Role

When the player reaches the pond in the middle of the crater, the forest will freeze and be completely covered in snow, thus giving the player access to the cave Kyurem is hiding. Once the player has captured or defeated Kyurem and left the area, the snow will disappear, and the northern portion of the caves will no longer be accessible. If Kyurem is defeated, however, the area will become accessible again after defeating the Pokémon League once more and returning to the pond in the center of the crater.

In the years between Black and White and Black 2 and White 2, the path from Lacunosa Town to the Giant Chasm has been blocked by a landslide. A lone boulder blocks the path, which can be pushed with Strength from the Giant Chasm's exterior.

In Black 2 and White 2, the player encounters Team Plasma here. Two Team Plasma Grunts block a path inside the east of the cave until the Plasma Frigate arrives on top of the crater's forest after the player obtains the Wave Badge. The frigate freezes over many of the trees, creating an icy hill on top of which the frigate is docked. Rood of the Seven Sages along with several old Team Plasma members confront the new Team Plasma; this gives the player the opportunity to sneak aboard the Plasma Frigate, where he or she battles against Colress and run into Ghetsis. The player follows Ghetsis out of the ship after defeating the Shadow Triad. At the end of the cave, Ghetsis appears and tries to freeze the player alive with Kyurem's Glaciate, but are saved by N and his ZekromB2/ReshiramW2 flying down from above. Ghetsis then reveals he tricked N into coming here so Ghetsis could fuse Kyurem with N's dragon. Ghetsis then uses his cane to control Kyurem, who then proceeds to fuse with N's dragon with the DNA Splicers, forcing the player to fight BlackB2/WhiteW2 Kyurem. Upon winning the battle, ZekromB2/ReshiramW2 will be separated from Kyurem and return to N, and Kyurem will disappear from the cave. Afterwards, the player fights Ghetsis himself.

After defeating Ghetsis, he goes into madness, causing the Shadow Triad to appear and take him away, leaving his cane. Outside, the Plasma Frigate has left. Rood and his team wait to tell the player that Colress has disbanded the new Team Plasma and taken the Plasma Frigate. Kyurem will appear here after the player has caught ZekromB2/ReshiramW2 at Dragonspiral Tower.

In the anime

In Pokémon Generations

Giant Chasm appeared in The King Returns, where Ghetsis was seen there with Kyurem, commanding it to cover all of Unova in ice. However, he was interrupted by N arriving with Reshiram, wanting to protect the place that had taught him how humans and Pokémon can live together. Ghetsis then used the DNA Splicers on Kyurem, allowing it to absorb Reshiram and turn into White Kyurem. He then ordered Kyurem to attack N, but N was saved by the sudden arrival of Hilbert and Zekrom, who had arrived to help stop Ghetsis.

Trivia

The Giant Chasm and its lore seem to have been inspired by the real-life Tunguska event. A shard of comet struck the Siberian taiga, forming a huge crater and felling trees for miles. Like how Kyurem is thought to have fallen on a comet, and how the Plasma Frigate destroys the forest, the Tunguska event is surrounded by conspiracy theories of aliens and weapons testing.